This invention relates generally to indicating apparatus for use in conjunction with a vehicular headlamp in order to enable the beam of the headlamp to be reaimed to a predetermined factory setting.
Modern headlamps include a fixed component and a movable component (e.g., a reflector) which is adapted to be adjusted about vertical and horizontal axes relative to the fixed component in order to establish proper aiming of the headlamp beam. At the vehicle assembly plant, the movable headlamp component is tilted about a horizontal axis to establish proper aim of the beam in a vertical direction and is tilted about a vertical axis to establish proper aim of the beam in horizontal or lateral direction. In some vehicles, the movable headlamp component carries an indicator in the form of a bubble level which, after the beam has been properly aimed in the vertical direction, is adjusted by vertical tilting in order to "zero" the bubble at the preset vertical position of the headlamp. The headlamp also includes a horizontal indicator which is calibrated to a zero setting once the beam has been factory set to the proper horizontal aim. If the headlamp subsequently becomes improperly aimed during service use, the two indicators may be used to determine when the lamp has been adjusted back to the factory preset position.
In prior headlamps, the two indicators are separate devices which often are located remotely from one another. As a result, reading of the indicators both during initial setting and during subsequent adjustment of the headlamp is inconvenient. Moreover, the provision of two separate indicators is relatively expensive.